The Gambit is accepted if black plays 3...dxe4. After that the main line is 4. Nc3 Nf6 5. f3, though there are many variations. After 5. f3 the Gambit splits into three main lines, the Kmoch Variation, the Keres Variation, and the Exchange variation, which are 5...Bb4, 5...c5, and 5...exf3 respectively.